Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757248Ab0FDD1K (ORCPT ); Thu, 3 Jun 2010 23:27:10 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:34630 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756749Ab0FDD1I (ORCPT ); Thu, 3 Jun 2010 23:27:08 -0400 X-Authority-Analysis: v=1.1 cv=xm0otvE9/LjRWYlyDrHfx7zP0/MGCmNk7gQgTP1ehto= c=1 sm=0 a=iHOon_RiDusA:10 a=UBIxAjGgU1YA:10 a=7U3hwN5JcxgA:10 a=Q9fys5e9bTEA:10 a=gMqfjgEr1zLu/65IO0LwxA==:17 a=VwQbUJbxAAAA:8 a=20KFwNOVAAAA:8 a=omOdbC7AAAAA:8 a=yPCof4ZbAAAA:8 a=meVymXHHAAAA:8 a=Z1bp_h1cUeaBkOXGOqsA:9 a=f6jLHrc0z4XScq6cKUQA:7 a=wosSKe_PEAYCy0FgTKeMDO_uNd8A:4 a=PUjeQqilurYA:10 a=jEp0ucaQiEUA:10 a=7DSvI1NPTFQA:10 a=0kPLrQdw3YYA:10 a=jeBq3FmKZ4MA:10 a=gMqfjgEr1zLu/65IO0LwxA==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.89.75 Subject: [PATCH v2][GIT PULL][v2.6.35] tracing/events: Convert format output to seq_file From: Steven Rostedt Reply-To: rostedt@goodmis.org To: LKML Cc: Ingo Molnar , Frederic Weisbecker , "Martin K. Petersen" , Kei Tokunaga , James Bottomley , Tomohiro Kusumi , Xiao Guangrong , Li Zefan In-Reply-To: <1275594103.15884.35.camel@gandalf.stny.rr.com> References: <1275594103.15884.35.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset="ISO-8859-15" Organization: Kihon Technologies Inc. Date: Thu, 03 Jun 2010 23:27:06 -0400 Message-ID: <1275622026.15884.72.camel@gandalf.stny.rr.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8070 Lines: 305 Ingo, Please pull the latest tip/perf/urgent-2 tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git tip/perf/urgent-2 Steven Rostedt (1): tracing/events: Convert format output to seq_file ---- kernel/trace/trace_events.c | 208 +++++++++++++++++++++++++++++-------------- 1 files changed, 141 insertions(+), 67 deletions(-) --------------------------- commit bcaa10360f3b2a623453a9fb10ef77aafeef8bb6 Author: Steven Rostedt Date: Thu Jun 3 15:21:34 2010 -0400 tracing/events: Convert format output to seq_file Two new events were added that broke the current format output. Both from the SCSI system: scsi_dispatch_cmd_done and scsi_dispatch_cmd_timeout The reason is that their print_fmt exceeded a page size. Since the output of the format used simple_read_from_buffer and trace_seq, it was limited to a page size in output. This patch converts the printing of the format of an event into seq_file, which allows greater than a page size to be shown. I diffed all event formats comparing the output with and without this patch. All matched except for the above two, which showed just: FORMAT TOO BIG without this patch, but now properly displays the output with this patch. v2: Remove updating *pos in seq start function. [ Thanks to Li Zefan for pointing that out ] Reviewed-by: Li Zefan Cc: Martin K. Petersen Cc: Kei Tokunaga Cc: James Bottomley Cc: Tomohiro Kusumi Cc: Xiao Guangrong Signed-off-by: Steven Rostedt diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 53cffc0..45a8968 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -29,6 +29,8 @@ DEFINE_MUTEX(event_mutex); LIST_HEAD(ftrace_events); +#define COMMON_FIELD_COUNT 5 + struct list_head * trace_get_fields(struct ftrace_event_call *event_call) { @@ -544,85 +546,155 @@ out: return ret; } -static ssize_t -event_format_read(struct file *filp, char __user *ubuf, size_t cnt, - loff_t *ppos) +enum { + FORMAT_HEADER = 1, + FORMAT_PRINTFMT = 2, +}; + +static void *f_next(struct seq_file *m, void *v, loff_t *pos) { - struct ftrace_event_call *call = filp->private_data; + struct ftrace_event_call *call = m->private; struct ftrace_event_field *field; struct list_head *head; - struct trace_seq *s; - int common_field_count = 5; - char *buf; - int r = 0; - - if (*ppos) - return 0; + loff_t index = *pos; - s = kmalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return -ENOMEM; + (*pos)++; - trace_seq_init(s); + head = trace_get_fields(call); - trace_seq_printf(s, "name: %s\n", call->name); - trace_seq_printf(s, "ID: %d\n", call->event.type); - trace_seq_printf(s, "format:\n"); + switch ((unsigned long)v) { + case FORMAT_HEADER: - head = trace_get_fields(call); - list_for_each_entry_reverse(field, head, link) { - /* - * Smartly shows the array type(except dynamic array). - * Normal: - * field:TYPE VAR - * If TYPE := TYPE[LEN], it is shown: - * field:TYPE VAR[LEN] - */ - const char *array_descriptor = strchr(field->type, '['); - - if (!strncmp(field->type, "__data_loc", 10)) - array_descriptor = NULL; - - if (!array_descriptor) { - r = trace_seq_printf(s, "\tfield:%s %s;\toffset:%u;" - "\tsize:%u;\tsigned:%d;\n", - field->type, field->name, field->offset, - field->size, !!field->is_signed); - } else { - r = trace_seq_printf(s, "\tfield:%.*s %s%s;\toffset:%u;" - "\tsize:%u;\tsigned:%d;\n", - (int)(array_descriptor - field->type), - field->type, field->name, - array_descriptor, field->offset, - field->size, !!field->is_signed); - } + if (unlikely(list_empty(head))) + return NULL; - if (--common_field_count == 0) - r = trace_seq_printf(s, "\n"); + field = list_entry(head->prev, struct ftrace_event_field, link); + return field; - if (!r) - break; + case FORMAT_PRINTFMT: + /* all done */ + return NULL; } - if (r) - r = trace_seq_printf(s, "\nprint fmt: %s\n", - call->print_fmt); + /* + * To separate common fields from event fields, the + * LSB is set on the first event field. Clear it in case. + */ + v = (void *)((unsigned long)v & ~1L); - if (!r) { - /* - * ug! The format output is bigger than a PAGE!! - */ - buf = "FORMAT TOO BIG\n"; - r = simple_read_from_buffer(ubuf, cnt, ppos, - buf, strlen(buf)); - goto out; + field = v; + if (field->link.prev == head) + return (void *)FORMAT_PRINTFMT; + + field = list_entry(field->link.prev, struct ftrace_event_field, link); + + /* Set the LSB to notify f_show to print an extra newline */ + if (index == COMMON_FIELD_COUNT) + field = (struct ftrace_event_field *) + ((unsigned long)field | 1); + + return field; +} + +static void *f_start(struct seq_file *m, loff_t *pos) +{ + loff_t l = 0; + void *p; + + /* Start by showing the header */ + if (!*pos) + return (void *)FORMAT_HEADER; + + p = (void *)FORMAT_HEADER; + do { + p = f_next(m, p, &l); + } while (p && l < *pos); + + return p; +} + +static int f_show(struct seq_file *m, void *v) +{ + struct ftrace_event_call *call = m->private; + struct ftrace_event_field *field; + const char *array_descriptor; + + switch ((unsigned long)v) { + case FORMAT_HEADER: + seq_printf(m, "name: %s\n", call->name); + seq_printf(m, "ID: %d\n", call->event.type); + seq_printf(m, "format:\n"); + return 0; + + case FORMAT_PRINTFMT: + seq_printf(m, "\nprint fmt: %s\n", + call->print_fmt); + return 0; } - r = simple_read_from_buffer(ubuf, cnt, ppos, - s->buffer, s->len); - out: - kfree(s); - return r; + /* + * To separate common fields from event fields, the + * LSB is set on the first event field. Clear it and + * print a newline if it is set. + */ + if ((unsigned long)v & 1) { + seq_putc(m, '\n'); + v = (void *)((unsigned long)v & ~1L); + } + + field = v; + + /* + * Smartly shows the array type(except dynamic array). + * Normal: + * field:TYPE VAR + * If TYPE := TYPE[LEN], it is shown: + * field:TYPE VAR[LEN] + */ + array_descriptor = strchr(field->type, '['); + + if (!strncmp(field->type, "__data_loc", 10)) + array_descriptor = NULL; + + if (!array_descriptor) + seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", + field->type, field->name, field->offset, + field->size, !!field->is_signed); + else + seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", + (int)(array_descriptor - field->type), + field->type, field->name, + array_descriptor, field->offset, + field->size, !!field->is_signed); + + return 0; +} + +static void f_stop(struct seq_file *m, void *p) +{ +} + +static const struct seq_operations trace_format_seq_ops = { + .start = f_start, + .next = f_next, + .stop = f_stop, + .show = f_show, +}; + +static int trace_format_open(struct inode *inode, struct file *file) +{ + struct ftrace_event_call *call = inode->i_private; + struct seq_file *m; + int ret; + + ret = seq_open(file, &trace_format_seq_ops); + if (ret < 0) + return ret; + + m = file->private_data; + m->private = call; + + return 0; } static ssize_t @@ -820,8 +892,10 @@ static const struct file_operations ftrace_enable_fops = { }; static const struct file_operations ftrace_event_format_fops = { - .open = tracing_open_generic, - .read = event_format_read, + .open = trace_format_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, }; static const struct file_operations ftrace_event_id_fops = { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/